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T Usami

Publications and source records attributed to T Usami.

53 records · Page 3Linked to original sources

[Three cases of infra-optic course of the anterior cerebral artery].

Three cases of rare anomalous cerebral artery originating from internal carotid at the level of ophthalmic artery to join the anterior cerebral artery were presented. Case 1. A 32-year-old woman was admitted following subarachnoid hemorrhages. Cerebral angiography disclosed the anterior communicating artery aneurysm and the anomalous vessel originating at rt. carotid siphon to join anterior cerebral artery. Case 2. A 37-year-old woman was admitted with rt. hemiparesis and aphasia. Cerebral angiography revealed the anomalous vessel originating at rt. carotid siphon to join contralateral anterior cerebral artery. Case 3. A 22-day-old male infant with enlarged head was admitted and cerebral angiography was performed. Anomalous vessel originating from internal carotid at the level of ophthalmic artery joined to the azygos anterior cerebral artery. There were only sixteen reported cases of this anomaly including our three cases. Seven aneurysms were associated in six cases, in which four were located in anterior communicating system. The fact that among the cases of this anomaly, ophthalmic artery used to not have normal stem but be fed from middle meningeal or middle cerebral artery suggested that the anomalous vessel had the common stem with ophthalmic artery at certain embryonic stage. These considerations led us to the conclusion that this anomalous vessel might originate from the remnant of anastomotic loop between primitive dorsal and ventral ophthalmic artery.

Adult↗

Relationship between contrast enhancement on computed tomography and cerebral vasospasm in patients with subarachnoid hemorrhage.

To elucidate the relationship between abnormal enhancement of the cisterns on computed tomography and cerebral vasospasm, we performed a systematic and prospective study in 60 patients with ruptured cerebral aneurysms. There is a significant relationship between the findings of contrast-enhanced computed tomography (CECT) within Day 3 of rupture and cerebral vasospasm. Among 37 patients undergoing CECT between Day 0 and Day 3, 17 (46%) showed prominent increases in density in the region around the circle of Willis and its branches. In 13 of 17 cases (76%), severe vasospasm with motor paralysis occurred. In the remaining 4 cases (24%) with only slight or no cerebral vasospasm, the hematoma in the subarachnoid space was removed surgically by Day 3. In 19 of 20 cases without remarkable CECT, no severe cerebral vasospasm with motor paralysis occurred. There is no significant relationship between the CECT findings after Day 3 and cerebral vasospasm. The results indicate that the prominent increase in density in the region of the circle of Willis and its branches often observed on CECT within Day 3 of subarachnoid hemorrhage is useful for prediction of the occurrence of cerebral vasospasm and also provide information on the pathogenesis of cerebral vasospasm.

Aged↗

Prevention of vasospasm by early operation with removal of subarachnoid blood.

Sixty-four patients who were operated on within 4 days after acute subarachnoid hemorrhage are included in this study. All patients underwent preoperative computed tomographic (CT) scanning, and the amount and distribution of subarachnoid blood clot were noted. Operation was carried out by the frontobasal lateral approach, and the subarachnoid clot was removed by microsurgical suction-irrigation after clipping of the aneurysm. Immediate postoperative CT scanning was performed to evaluate the completeness of the subarachnoid blood clot removal. The presence or absence of postoperative vasospasm was determined with angiography performed between the 7th and 10th postoperative days. All patients were, of course, also evaluated for evidence of neurological deterioration. Approximately two-thirds of the patients in this series showed high density subarachnoid blood clot on the preoperative CT scan. The postoperative CT scans showed that it was possible to remove the majority of the blood clot except that located in the frontal interhemispheric fissure, the posterior part of the insular cistern on the approached side, and all of the insular cistern on the contralateral side. There was no spasm or only mild spasm in any site where the blood clot had been successfully removed. Delayed neurological deficits occurred only in those cases in which subarachnoid blood clot remained in the cisterns. These results suggest that it is possible to prevent intracranial arterial spasm and associated neurological deterioration by early operation and removal of clotted blood from the subarachnoid space.

Adult↗

Regional variations in the incidence of end-stage renal failure in Japan.

CONTEXT: Despite recent medical advances, the number of patients beginning dialysis annually is increasing in both the United States and Japan. The ethnically homogeneous population of Japan presents an opportunity to study the presence of factors other than race/ethnicity that might contribute to incidence of end-stage renal disease (ESRD). OBJECTIVE: To determine if and where regional differences exist in ESRD in Japan. DESIGN, SETTING, AND SUBJECTS: Analysis of data reported by the Japanese Society for Dialysis Therapy based on the annual number of patients with ESRD beginning maintenance dialysis therapy in all 47 prefectures of Japan from 1982 to 1998. MAIN OUTCOME MEASURES: Mean annual ESRD incidence and increasing rate of ESRD in each of 11 predefined areas making up the entire country. RESULTS: Incidence of ESRD increased approximately 3-fold in Japan during the study years, from 81.3 per 1 million in 1982 to 237.6 per 1 million in 1998. Significant regional differences were found in both measures. The mean (SEM) annual ESRD incidence (P<.01) and increasing rate of ESRD (P<.01), respectively, were significantly different across Japan. Koshinetsu (140 [11] per 1 million and 9.1 [0.6] per 1 million/y) and Hokuriku (141 [12] per 1 million and 9.7 [0.5] per 1 million/y) were the areas with the lowest incidence and increasing rate of incidence, while Okinawa (188 [17] per 1 million and 13.4 [0.6] per 1 million/y) and Kyushu (179 [15] per 1 million and 12.0 [0.6] per 1 million/y) were the areas with the highest incidence and increasing rate of incidence. CONCLUSIONS: We found definite and significant regional differences in incidence and increasing rate of incidence of ESRD in Japan. Further analyses are needed to identify factors that contribute to these regional differences and thereby improve strategies for treatment of renal disease. JAMA. 2000;284:2622-2624.

Analysis of Variance↗